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Students, in pairs, will slide blocks down different materials at their desks, to test different materials for the amount of friction.

Explain procedure: Set up your cardboard ramp, and slide two blocks together, to test out your set up. They should go down at about the same speed. Then clip different materials onto the ramp, and compare the friction of each of the materials by sliding a two blocks down at the same time. Slide the blocks a few times to make sure you are getting a good result.
Compare cardboard and cloth. Then try cloth and sandpaper. Then sandpaper and cardboard. (Optional: compare ice with the other materials.)
Each time, record which material has the most and which has the least friction on your worksheet.

If students get done early, they can change how the ramp is set up e.g. height, and try sliding blocks again.

Summarize what kinds of surface increase and reduce friction (5 mins)
Ask students to bring their cardboard, cloth and sandpaper to the carpet.
Which surface had less and more friction for each pair?
Feel the surfaces and talk about why they have the least and most friction.
Bumpy surfaces rub against the block more, and slow it down more.
Write on board: under less friction put smoother surface, under more friction put bumpier surface.

Prepare the foam frames in advance.

Students each build a simple catapult. (Stretch the elastic band over the arms of the foam core. Use the piece of stick to twist up the rubber band, then slide the spoon in, orienting it so that it acts as the arm of the catapult).
While staying behind a line, fire balls of tin foil, and record how far they go.
After some time, ask what students did to make the balls go the furthest. (Direction of the force, strength of the force by pulling the spoon back more or less, weight/size of the object being fired, strength of the force by twisting the rubber band more or less).
Then more time to try out other students’ suggestions. Ask them to think about the forces on the paper ball.
Discussion on the forces involved in each stage of the catapult firing (force from hand to pull back the spoon, force in the elastic band (potential energy), force as the elastic band unwinds and moves the spoon, force of the spoon on the foil ball, gravity pulling the foil ball to the ground). There is a chain of forces.

Students can measure and record on a graph how far their ammuntion goes.

More details on catapult forces:
It is called a torsion catapult. (In the twisted band - a twising force is called torsion).

Types of Motion for younger students
Ask students to use their bodies and the equipment to move in different ways: spin, roll, slide, lift, fall, bounce, swing. They can also be given balls to use. They can use a worksheet to check off each motion, and draw the equipment they used.

Forces for younger students
Before the students use the equipment, discuss what a force is: something that can move an object, or stop it from moving. A push or a pull.
Sometimes a push or a pull is when things are in contact with each other, like my hand pushing the ground , or my linked fingers pulling against each other (demonstrate and ask students to try).
Sometimes the force does not contact the object it moves. Gravity pulls things towards the ground, even if it is not touching them.

Organize the students into groups, and show them the pieces of equipment that they will be using.
For example, divide playground equipment into two or three stations, then add one or two other stations (e.g. bouncing balls, balancing pole).
Ask students to feel the forces on their body, find out why they move up or down, what forces make them move.
As the students are using the equipment, visit each station help students feel a force as it happens.
After all students have visited all stations review what they found.

SLIDE forces, questions to ask and discussion points:
What are the pushes and pulls as you use the slide? Why can’t you slide up? [gravity is pulling you down, but you can walk up and push against it]. What happens if you start half way down the slide - how do the forces change?
As you climb up the steps you work against gravity, giving yourself energy. Gravity pulls you back down.
Friction between you and the slide slows you down, so the clothes you wear or how wet it is makes a difference to how fast you can go.

SWINGS forces, questions to ask and discussion points:
How do you start off. What kind of force? (what is pushing or pulling)?
Why do you stop at the top of a swing. What force makes you stop? [gravity pulling you back down].
How to get higher?
Push of your foot against the ground, or someone pushing you makes you start to move. You can pump your legs to make yourself go higher (putting your legs higher gives you more height energy, like the slide).
Gravity pulls you back down. The higher you went the longer you have coming down and the faster you will go.

CLIMBING NET forces, questions to ask and discussion points:
What forces make it stay up? Look at it as a structure, like a bridge or building.
You tread on the rope and push on it. Why doesn’t it move much?
Can you feel the forces of someone else moving around on the net?
Discussion:
The ropes constantly have pushes and pulls on them. They pull against the fasteners which pull back on the ropes. This keeps the whole thing taught.
If you move, you make a push, which transmits through the ropes to the other end of the structure, where someone else can feel it.
Bridges and other man-made structures are built to spread out the forces on them so they stay up. They have lots of cross braces connecting all the parts together.

The lesson adds in other stations.

Energy transformation for older students
Divide the students into groups, to rotate through the different pieces of equipment. List different kinds of energy and discuss the kinds of energy that might be used on the equipment. Then as the students use the equipment, talk to them about the energy types that are being used and how they are converting between each other: motion energy as their body is moving, potential energy as they get higher up, heat energy made in their bodies as they are moving, chemical energy stored in their bodies that can be converted to all these other kinds of energy.

A SWING has motion energy as it moves, which changes to potential energy (or "height energy") as it gets higher. Each time the swing goes back and forth, it has the most motion energy at the bottom of the swing, and the least when it comes to a stop at the top of its swing. It has the most potential energy when it is highest and the least when it is lowest. Energy changes between motion and potential energy forms and back again, as it swings back and forth. This demonstrates that energy can be transferred, but is always conserved.

A SLIDE converts potential energy to motion energy. As you climb the steps you gain potential energy (from gravity pulling on you). As you slide downwards, the potential energy reduces, and is converted to motion energy.

Additional force of friction on the slide:
A slide is an inclined plane, so the gravity pulling you down presses you onto the slide. As you move, there is friction between you and the slide. Friction is a force that slows things down as objects rub together. The rubbing generates heat energy, which is quickly lost to the air. Students with bare legs may feel that heat energy made from the friction between their body and the slide. Energy is transferred but always conserved.
As some of the potential energy you had at the top of the slide is lost to friction as you slide down, you descend more slowly than if you simply jump from the top of the slide.
Slides are made of smooth material to reduce friction. Students can experiment sliding on different pieces of cloth, or onto of jackets etc, to experiment with which materials reduce the friction most, and allow them to go the fastest down the slide.

A SPINNER has rotational energy.
Ask students to compare how fast they move when they sit on the outside or the middle of the spinner. They move much faster on the outside as they travel further in the same time as someone sitting in the middle of the spinner (look at one rotation to compare).
You can feel the force pushing you outwards as you hang on to the spinner. If you let go of the spinner, you would fly off, but in a straight line from your direction of travel, rather than straight outwards (as dictated by Newton's First Law: objects will keep moving in a straight line unless acted on by another force).

The lesson adds in other stations.

Newton's Laws for older students
Students can use the equipment and find where the Laws happen.
1st Law - Objects will stay stopped or in constant motion until a force acts on them (e.g. push off a step to move upwards, push the ground to start the swing)
2nd Law - F=ma: for a constant force, a small mass will accelerate more than a large one, and for the same mass, increasing the force increases its acceleration (e.g. pushing a friend harder on a swing will make them swing further)
3rd Law - For every action there is an equal and opposite reaction (e.g. when pushing down on a step, it pushes back making you move upwards, the step itself does not move)

Types of motion, for younger students
Use the balls to learn about different kinds of motion. The students are instructed to move the balls in various ways, to make them move through various motions: spin, roll, slide, lift, fall, bounce, swing.
Discuss where the force comes from (the "push or pull") that made the ball do each motion.
The students' hands will provide the force to make the balls spin, roll or slide.
The force of gravity will pull the ball down to make it fall or bounce.
When the ball bounces, the floor pushes up on the ball to make it go up again.
For the swing, the push and pull of an arm makes it move, and gravity is pulling down on the arm - you can feel it.

Energy and momentum in a double ball bounce
Bounce a basketball or a tennis ball. They both start with gravitational potential energy ("height energy") when they are held up high. This gravitational potential energy changes into motion energy as the ball falls. As the ball hits the ground the motion energy becomes elastic potential energy, as the energy is stored in the flexible material of the ball. This elastic energy is converted back to motion energy as the ball moves upwards again, which is converted back to all gravitational potential energy as the ball reaches the top of its bounce. The ball does not bounce as high each time, as energy is lost as heat as it rubs agains the air, and as the material of the ball flexes on the ground.

Now stack the tennis ball on top of the basketball and release them both at the same time. The tennis ball will fly really high (or sideways) as it bounces off the basketball. The basketball gives its energy to the tennis ball and so does not bounce up much at all.
The basketball is larger, so has more momentum (speed and mass combined) than the tennis ball as they fall. When the basketball bounces up it transfers its momentum to the tennis ball. As the total momentum is the same when it is transferred between the balls, but the tennis ball is a lot smaller than the basketball, the tennis ball will move a lot faster. So the tennis ball bounces back up with its own momentum plus the momentum of the basketball, which makes it move really fast. The basketball loses its momentum, so hardly moves upwards at all.
Students can experiment with more than two balls, balls of different sizes etc. They will run around a lot.

Discuss what worms need to survive (ideally through close observation of a worm)
Air: the bin has holes in the lid, and the lid will be opened frequently to allow more air in too.
Water: worms need to stay moist (as they breathe through their skin, obtaining the oxygen dissolved in the water)
Food: worms eat rotting plants which are soft enough for the worm to ingest (and turn them into rich soil)
Darkness: worms burrow down away from the light to seek cool, damp places, and to hide from predators

Assemble the bin as a class
Sit the class in a circle around the empty worm bin, and assemble the bin step by step to provide the worms with what they need to survive.
1. Worms need a moist environment - make a layer of wet newspaper in the bottom of the bin to keep the environment damp: distribute trays of water around the circle. Distribute a sheet of newspaper to each student. Ask the students to lay their newspaper sheet in the water, then crumple it into a loose ball (about 5-10cm diameter) to gently squeeze the extra water out. Pass around the worm bin for students to add their wet newspaper balls to it, to make a layer of wet newspaper balls covering the bottom of the bin.
2. Add the worms: add the red wigglers/small garden worms in a little soil. (Students can also add worms they have been looking closely at.)
3. Worms need food: students can each add a piece of old vegetable to the bin, to form a scant layer. Do not add to much as mould growth on the uneaten vegetables can take over the worm bin. Avoid sweet fruits (apple cores, banana peels, orange peels) as this attracts fruit flies.
4. Cover the soil to keep it moist: students tear newspaper into long strips, then layer this on top of the worms and their food. This keeps the moisture in and any fruit flies out. It also makes a dark space for worms to crawl around in and find food.
5. Place the lid on. Air will enter through small holes in the lid, or a tightly-sealing lid should be opened periodically to let fresh air in.

Discuss long term care of the worms
The bin should be kept out of direct sunlight and away from heaters, to keep it cool.
Food should be added when the worms have consumed the previous food. Too much food will invite mould growth.
The bin should be kept damp but not soggy: worms need to stay moist, but will drown in too much water. Any added water should be chlorine-free.
When the newspaper strips are getting broken up, mix them in and add a new layer on top.
After a month or so, the worms will have made new, rich soil from the vegetable scraps. This soil can be added to garden or potted plants as fertilizer.
Sometimes, plants will grow from the seeds added to the bin (see third photo).

See the worm bin care sheet for more detailed information (attached).
Also more information here: http://compost.css.cornell.edu/worms/moreworms.html

Dismantling the worm bin
When the worm bin is taken down, the freshly made compost/rich earth can be separated from the worms and put on plants that need fertilizing.
Look out for baby worms, and even worm eggs (about 1mm long, dark red-brown and egg shaped with one pointed tip) - see photo.
The worms can be put in a garden, or kept to make a new worm compost bin.

Setting up a second compost bin, from a previously made compost bin:
As above, make a layer of wet balls of newspaper in the bottom of the new bin. Take several handfuls of soil, rich with worms, from the old compost bin (you could use the entire bottom layer of soil and worms if this layer is not too deep). Layer over the old vegetables and dry newspaper etc, as described in the instructions above.

Before handing out the worms. practice using magnifier; look at the lines on your finger.
Look more closely at worms and how their body structure helps them survive in their habitat.

Hand out one worm per student enclosed in a small petri dish with a film of water in the bottom.
Ask students to draw what they see (not what they think they see).
After a while, ask the students what they have noticed. Ask if they noticed the segments, how they move, the blood vessel, the dark soil in the gut, which is head and tail.
Allow more time for the drawing.

Show image of worm and relate to what students have found, and which body parts are similar and different to ours.
Head, tail, mouth, anus, segments, clitellum, blood vessel. Organs: heart, brain, blood vessels.
Try this link for an image: https://thebiologynotes.com/nervous-system-of-earthworm/

How do worms breathe?
We breathe by pulling air into our lungs. Worms breathe through their skin, by absorbing the oxygen from water - hence they need to stay moist to keep getting oxygen.

How do worms see? (There is no obvious eye).
Although we can't see any eyes on a worm, they do have rudimentary eyes. Eyes closed activity to show how worms see: ask students to look up at the light, then close their eyes and notice that they can still see some brightness. While keeping their eyes closed, face away from the light and notice how the light dims. Worms are able to detect where the light is with rudimentary eyes - they cannot focus to see an image but can detect which direction the light is coming from. This allows them to dig down into the soil (away from the light) to avoid predators.

How do worms move?
They move by muscle contraction and by gripping with the bristles (called setae) on each segment.
See these images to show the sequential muscle contractions that move them along:
https://www.macmillanhighered.com/BrainHoney/Resource/6716/digital_firs…
https://www.researchgate.net/figure/Earthworm-Locomotion-Mechanism-adap…

Other worm information:
They are both male and female in the same body but still need to mate to reproduce, by joining clitella (the smooth band on their bodies near the head).
They are decomposers, eating dead plant and animal matter and turning it into soil. They also aerate soil as they dig through it, making it more habitable for plant roots and other soil animals.

States of matter in water demonstration
1. Here is an ice cube (or give each student one). Is it solid, liquid or gas? Why? Fixed size, fixed shape.
What is happening to it? Melting. It is changing to a liquid because it is getting warm in the hand. The molecules are moving apart enough that they can flow past each other and make drips of liquid.
The name for a solid changing into a liquid is Melting.
2. Now we start with liquid water. We can turn it into a gas by warming it up even more - give it more energy. Use a see-through kettle or a hot plate to boil water.
What is happening to the liquid? Bubbles of gas are forming in it. It has enough energy to heat it up enough to turn to gas. The name for a liquid turning into a gas is Evaporation. (Alternatively, spread a drop of water on black paper and in a warm classroom or in the sun you can watch it evaporate.)
3. Now we will turn the gas back into a liquid by cooling it down. Put a glass lid/bowl over steam escaping from hot water - see droplets of water forming inside the glass. Why do the drops form on the glass? Because it is cooler, and they lose enough energy to move more slowly and become water again. The name for a gas turning into a liquid is Condensation.
4. How can we make the liquid turn back into a solid?
Cool it down even further. Optional: make frost on the outside of a can: www.ingridscience.ca/node/227 (set up at the start of the lesson - it takes 15 mins to form). Name for a liquid to a solid is Freezing.

Measure the temperature of water in each state
1. Measure the temperature of ice:
Half fill a styrofoam cup with ice cubes, then immerse a thermometer in it. Read the temperature once it has stabilized (maybe a few minutes). If the thermometers are properly immersed in the ice they should read 0°C or below. Students can add their temperature reading to a graph on the board. Explain that ice forms at 0°C and remains solid at any temperature below that.
2. Measure the temperature of liquid water:
Pour water into the cups by mixing boiling and cold water to vary the warmth of the water in each cup. Ask students to measure the temperature of their water, and add it to a graph on the board. All measurements should read between 0°C (the melting point of water) and 100°C (the boiling point of water).
3. Measure the temperature of liquid water boiling:
This should be a demonstration. Using heat proof tongs, dip a thermometer into the water as it comes to the boil. Ask one student to read out the temperature as it rises to 100°C (the boiling point of water). If the thermometer can be held in while it continues to boil it may rise above 100°C, as more and more bubbles of gas form within the water.
4. Optional: graph the temperature data. Liquid water will always be between 0°C and 100°C. Ice will be at or below 0°C. The gas in boiling water can be above 100°C.